##Stitching圖像拼接 圖像拼接stitching是OpenCV2.4.0出現的一個新模塊，所有的相關函數都被封裝在Stitcher類當中。關于Stitcher類的詳細介紹，可以參考：?[http://docs.opencv.org/2.4.2/modules/stitching/doc/high_level.html?highlight=stitcher#stitcher](http://docs.opencv.org/2.4.2/modules/stitching/doc/high_level.html?highlight=stitcher#stitcher)。 這個類當中我們主要用到的成員函數有createDefault，用于創建缺省參數的stitcher；estimateTransform，用于 生成最后的拼接圖像；而對于composePanorama和stitch，文檔中提示如果對stitching的整過過程不熟悉的話，最好不要使用以上 兩個函數，直接使用stitch就行了。整個拼接的算法實現過程十分復雜，其中涉及到圖像特征點的提取和匹配、攝像機的校準、圖像融合、圖像的變形、曝光 補償等算法的結合。 說得這么復雜，但實際上這些模塊的接口調用，OpenCV都為我們搞定了，我們只需要調用createDefault函數生成默認的參數，再使用stitch函數進行拼接就ok了。 圖像拼接的實例代碼如下，在VS2013平臺上運行成功： ~~~ /*M/////////////////////////////////////////////////////////////////////////////////////// // // IMPORTANT: READ BEFORE DOWNLOADING, COPYING, INSTALLING OR USING. // // By downloading, copying, installing or using the software you agree to this license. // If you do not agree to this license, do not download, install, // copy or use the software. // // // License Agreement // For Open Source Computer Vision Library // // Copyright (C) 2000-2008, Intel Corporation, all rights reserved. // Copyright (C) 2009, Willow Garage Inc., all rights reserved. // Third party copyrights are property of their respective owners. // // Redistribution and use in source and binary forms, with or without modification, // are permitted provided that the following conditions are met: // // * Redistribution's of source code must retain the above copyright notice, // this list of conditions and the following disclaimer. // // * Redistribution's in binary form must reproduce the above copyright notice, // this list of conditions and the following disclaimer in the documentation // and/or other materials provided with the distribution. // // * The name of the copyright holders may not be used to endorse or promote products // derived from this software without specific prior written permission. // // This software is provided by the copyright holders and contributors "as is" and // any express or implied warranties, including, but not limited to, the implied // warranties of merchantability and fitness for a particular purpose are disclaimed. // In no event shall the Intel Corporation or contributors be liable for any direct, // indirect, incidental, special, exemplary, or consequential damages // (including, but not limited to, procurement of substitute goods or services; // loss of use, data, or profits; or business interruption) however caused // and on any theory of liability, whether in contract, strict liability, // or tort (including negligence or otherwise) arising in any way out of // the use of this software, even if advised of the possibility of such damage. // //M*/ #include <iostream> #include <fstream> #include "opencv2/highgui/highgui.hpp" #include "opencv2/stitching/stitcher.hpp" using namespace std; using namespace cv; bool try_use_gpu = false; vector<Mat> imgs; string result_name = "result.jpg"; // 默認輸出文件名及格式 void printUsage(); int parseCmdArgs(int argc, char** argv); int main(int argc, char* argv[]) { int retval = parseCmdArgs(argc, argv); if (retval) return -1; Mat pano; Stitcher stitcher = Stitcher::createDefault(try_use_gpu); Stitcher::Status status = stitcher.stitch(imgs, pano); if (status != Stitcher::OK) { cout << "Can't stitch images, error code = " << status << endl; return -1; } imwrite(result_name, pano); return 0; } void printUsage() { cout << "Rotation model images stitcher.\n\n" "stitching img1 img2 [...imgN]\n\n" "Flags:\n" " --try_use_gpu (yes|no)\n" " Try to use GPU. The default value is 'no'. All default values\n" " are for CPU mode.\n" " --output <result_img>\n" " The default is 'result.jpg'.\n"; } int parseCmdArgs(int argc, char** argv) { if (argc == 1) { printUsage(); return -1; } for (int i = 1; i < argc; ++i) { if (string(argv[i]) == "--help" || string(argv[i]) == "/?") { printUsage(); return -1; } else if (string(argv[i]) == "--try_use_gpu") // 默認不使用gpu加速 { if (string(argv[i + 1]) == "no") try_use_gpu = false; else if (string(argv[i + 1]) == "yes") try_use_gpu = true; else { cout << "Bad --try_use_gpu flag value\n"; return -1; } i++; } else if (string(argv[i]) == "--output") // 若定義了輸出圖像名，則更改result_name { result_name = argv[i + 1]; i++; } else { Mat img = imread(argv[i]); if (img.empty()) { cout << "Can't read image '" << argv[i] << "'\n"; return -1; } imgs.push_back(img); } } return 0; } ~~~ 這里在自己的機子上實現簡單的圖像拼接，程序生成的可執行文件名為imageStitching.exe，如果直接運行程序將直接退出，需要在cmd中進行以下操作： 找到imageStitching.exe所在的目錄，在終端里輸入imageStitching+**被拼接的圖像路徑**（若與imageStitching.exe在同個文件夾，直接輸入圖像的名字和后綴名即可），如這里輸入:imageStitching 1.jpg 2.jpg 3.jpg。  若輸入：–output 4.jpg，就會把1.jpg、2.jpg和3.jpg 進行拼接，而輸出的文件是imageStitching.exe路徑下的4.jpg，由于在例程默認輸出為result.jpg，可以不用設置output。? 由于選取的圖像在拍攝時并不平行，能拼接出這種效果的圖像已是不錯： 1.jpg：?  2.jpg：?  3.jpg：?  拼接輸出結果result.jpg：?  代碼中使用函數：`Stitcher::Status status = stitcher.stitch(imgs, pano);`就能得出一個傻瓜拼接結果…如之前所提到的，這其中涉及到很多算法的實現過程，可以看到圖像拼接算法是一個值得深入的領域。更多的算法可參考：? [http://academy.nearsoft.com/project-updates/makingapanoramapicture](http://academy.nearsoft.com/project-updates/makingapanoramapicture)